Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 248 AM EDT Wed Jun 18 2025 Valid 12Z Wed Jun 18 2025 - 12Z Fri Jun 20 2025 ...Severe thunderstorm risks for the Midwest & lower Great Lakes on Wednesday, & the Mid-Atlantic States Thursday... ...Fire weather concerns and/or significant heat for portions of the West, Rockies, & Central High Plains through Friday... ...Heat builds in the East through Thursday... The weather maker for the eastern half of the country through Friday will be a progressive upper level disturbance and cold front pushing across the Plains and the East. A wave of low pressure wave in the Plains is forecast to intensify and track northeast through the Midwest on Wednesday, which brings a threat of severe thunderstorms and flash flooding from the southern Plains across the Midwest/Ohio Valley and into the Great Lakes. The Appalachians, Mid-Atlantic states, and New England states will see increasing heat through Thursday as a ridge of high pressure briefly builds across the region and a warm front lifts north of the area. Record high temperatures...in the mid 90s...are possible in southern New England on Thursday. Once the cold front nears the East on Thursday, more widespread severe weather would be possible within the increasingly hot and humid air mass across the Mid-Atlantic States and New England. A waning area of thunderstorms is expected with time as a cold front leads to cooling and dries things out, clearing the Midwest by Thursday and the Mid-Atlantic and New England states by Friday. The Gulf Coast and Southeast maintain scattered showers and thunderstorms for the remainder of the work week. A deep layer cyclone moves southeast with time out of the northeast Pacific, with the center moving into the Pacific Northwest on Friday. It will drive a cold front east and south through the Pacific Northwest and Montana by Friday morning. The combination of windy and dry conditions brings an elevated fire weather threat across interior portions of the Northwest on Wednesday (where Red Flag Warnings are in effect), which shifts into the Great Basin on Thursday and Friday (Red Flag Warnings are in effect for much of Utah). Significant heat expands across the West into the Central High Plains on Wednesday through Friday ahead of the cold front as the ridge rebuilds ahead of the deep layer cyclone, threatening daily record high temperatures across portions of the Great Basin and western South Dakota on Thursday and from Colorado north and east into Nebraska and South Dakota on Friday. High temperatures will remain 100F+ for the Desert Southwest through the remainder of the work week (Death Valley could exceed 120F) where Extreme Heat Warnings remain in effect. Heat Advisories remain in effect for southern and western fringes of the Big Bend of western Texas on Wednesday where high temperatures of 100-110F are forecast. Roth/Miller Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php